Salt River Valley (SRV) Regional Model

Salt River Valley Model History and Timeline

SRV MODFLOW model development began in the late 1980's. Previous to the late 1980's, two groundwater models within the Salt River Valley had been developed. Thomas Anderson (1968) developed an electric analog model simulating the groundwater depletion of Central Arizona between 1923 and 1964. In 1982 Long et al. developed a USGS Trescott Model which simulated 1964 - 1977.

Since the first SRV MODFLOW release in 1994 the model has undergone several updates with the most recent update completed in 2009 (transient calibration period 1983-2006). The SRV model geology was updated in 2010 and expanded the model grid to include the Hassayampa sub-basin. The next SRV model update is currently in the initial phase of development and plans to include a simulation of steady state (circa 1900) and transient (1901-2011) conditions.

Metadata: Report No. 16 documents ADWR's 2006 update of the geologic framework of its Salt River Valley (SRV) groundwater flow model. The purpose of the geology update was to incorporate new geologic information from active growth areas within the model area, and to better define geologic interpretations throughout the model area.

East Valley Water Forum Scenarios for the East Salt River Valley Sub-basin. An Application of the Regional Groundwater Flow Model of the Salt River Valley, Arizona. Hipke, W. Modeling Report No. 17. (April 2007) [7.7MB pdf]

Metadata: Report No. 17 used the Salt River Valley 1983-2002 groundwater flow model to run predictive scenarios developed by the East Valley Water Forum for the East Salt River Valley sub-basin portion of the Phoenix AMA. The scenarios were designed to provide information for the development of a water management plan by the East Valley Water Forum. The three scenarios include a “business as usual” scenario, a balance between pumping and recharge scenario, and the last scenario looked at possible solutions to reducing the major cones of depression predicted by the first two scenarios.

Metadata: Report No. 19 documents ADWR's 2008/2009 update of the SRV Regional groundwater flow model (1983-2006). The model was developed and calibrated during the transient period and does not include any future projections. The 2009 SRV model update includes the following improvements: simulates conditions between 1983 and 2006, decreases the model cell size to 0.5 mile by 0.5 mile, updates geologic interpretation, adds the Lake Pleasant region, revises pumpage and recharge datasets, and uses an updated MODFLOW code. In addition to the model updates, the model was re-calibrated using well specific heads and the annual water budget for the transient period of 1983 to 2006.

Metadata: Report No. 22 documents the details of various 100-year predictive scenarios that were developed as part of the Assured Water Supply re-designation process. This document discusses assumptions common to all scenarios, assumptions specific to each scenario, the variations in pumping and recharge volumes used in the scenarios, and the results of the scenarios.

Metadata: Report No. 23 documents ADWR's 2009/2010 merging of the Lower Hassayampa sub-basin geology with the geology used in the 2009 SRV regional groundwater flow model from 1983-2006 (Report No. 19), as well as the revisions north of Paradise Valley, adjacent to the Hieroglyphic Mountains, and in the Buckeye and Surprise areas. The geology data presented in this report will be used in the "Phoenix model" which is currently in production at ADWR. The Phoenix model combines the SRV and Lower Hassayampa sub-basin model domains into one model domain.